Patient preferences and acceptable risk for computed tomography in trauma

Diagnostic testing in children: A qualitative study of pediatricians' considerations

AIMS AND OBJECTIVES

Studies in adult medicine have shown that physicians base testing decisions on the patient's clinical condition but also consider other factors, including local practice or patient expectations. In pediatrics, physicians and parents jointly decide on behalf of a (young) child. This might demand more explicit and more complex deliberations, with sometimes conflicting interests. We explored pediatricians' considerations in diagnostic test ordering and the factors that influence their deliberation.

METHOD

We performed in-depth, semistructured interviews with a purposively selected heterogeneous sample of 20 Dutch pediatricians. We analyzed transcribed interviews inductively using a constant comparative approach, and clustered data across interviews to derive common themes.

RESULTS

Pediatricians perceived test-related burden in children higher compared with adults, and reported that avoiding an unjustified burden causes them to be more restrictive and deliberate in test ordering. They felt conflicted when parents desired testing or when guidelines recommended diagnostic tests pediatricians perceived as unnecessary. When parents demanded testing, they would explore parental concern, educate parents about harms and alternative explanations of symptoms, and advocate watchful waiting. Yet they reported sometimes performing tests to appease parents or to comply with guidelines, because of feared personal consequences in the case of adverse outcomes.

CONCLUSION

We obtained an overview of the considerations that are weighed in pediatric test decisions. The comparatively strong focus on prevention of harm motivates pediatricians to critically appraise the added value of testing and drivers of low-value testing. Pediatricians' relatively restrictive approach to testing could provide an example for other disciplines. Improved guidelines and physician and patient education could help to withstand the perceived pressure to test.

Predictors of patient preference for either whole body magnetic resonance imaging (WB-MRI) or CT/ PET-CT for staging colorectal or lung cancer

INTRODUCTION

Whole body magnetic resonance imaging (WB-MRI) may be more efficient in staging cancers, but can be harder for patients to tolerate. We examined predictors of patient preference for WB-MRI vs. CT/ PET-CT for staging colorectal or lung cancer.

METHODS

Patients recruited prospectively to two multicentre trials comparing diagnostic accuracy of WB-MRI with standard staging scans were sent two questionnaires: the first, administered at trial registration, captured demographics, educational level and comorbidities; the second, administered after staging completion, measured emotional distress (GHQ-12), positive mood (PANAS), perceived scan burden, patients' beliefs about WB-MRI, and preference for either WB-MRI or CT (colorectal trial), WB-MRI or PET-CT (lung trial). Preference for WB-MRI or CT/ PET-CT was analysed using logistic regression.

RESULTS

Baseline and post-staging questionnaires were completed by 97 and 107 patients, respectively. Overall, 56/107 (52%) preferred WB-MRI over standard scans and were more likely to have no additional comorbidities, higher positive mood, greater awareness of potential benefits of WB-MRI and lower levels of perceived WB-MRI scan burden. In adjusted analyses, only awareness of potential WB-MRI benefits remained a significant predictor (OR: 1.516, 95% CIs 1.006-2.284, P = 0.047). Knowledge that WB-MRI does not use radiation predicted preference (adjusted OR: 3.018, 95% CIs 1.099-8.288, P = 0.032), although only 45/107 (42%) patients were aware of this attribute.

CONCLUSIONS

A small majority of patients undergoing staging of colorectal or lung cancer prefer WB-MRI to CT/ PET-CT. Raising awareness of the potential benefits of WB-MRI, notably lack of ionizing radiation, could influence preference.

[Success, satisfaction and improvement of informed consents for computed tomography : A survey among patients and physicians]

Hintergrund

Die Aufklärung eines Patienten vor einer Computertomographie (CT) spielt sowohl für die aufklärenden Ärzte als auch für die Patienten eine entscheidende Rolle. Ein persönliches Aufklärungsgespräch über die Durchführung, Risiken und mögliche Alternativen ist vor einer CT-Untersuchung verpflichtend.

Methode

Durchgeführt wurde eine Befragung zur Patientenzufriedenheit hinsichtlich der Dauer und den Inhalten einer CT-Aufklärung. Befragt wurden hierüber auch aufklärende Ärzte. Ein weiterer Teil der Befragung beschäftigte sich mit der Akzeptanz technischer Hilfsmittel, wie z. B. Informationsvideos oder Tablets/PCs.

Ergebnis

Insgesamt 512 Patienten und 106 Ärzte beteiligten sich an der Befragung. Die Dauer des Aufklärungsgesprächs gaben die Patienten mit durchschnittlich 4,08 min und die Ärzte mit 4,7 min an. Am ausführlichsten klärten die Ärzte über die Nebenwirkungen von Kontrastmitteln auf. Über mögliche Alternativen und die Notwendigkeit der Untersuchung wurde weniger aufgeklärt. Korrelierend erinnerten sich rund 92 % aller Patienten nicht an eine Information über alternative Untersuchungsmöglichkeiten. 88,7 % der Patienten und 95,3 % der ärztlichen Teilnehmer befürworteten die Aufklärung mithilfe von interaktiven Videos und Animationen und 74 % der Patienten sowie 98,8 % der Ärzte die Beantwortung der Fragen zum Gesundheitszustand am Tablet/PC.

Schlussfolgerung

Die Dauer einer CT-Aufklärung wurde von den Patienten etwas kürzer eingeschätzt, wobei sich die Patienten teilweise nur schlecht an die Aufklärungsinhalte erinnerten. Die Akzeptanz gegenüber technischen Neuerungen war bei den Teilnehmern sehr hoch. Durch den Einsatz von Informationsvideos und Tablets/PCs könnte der Aufklärungserfolg erhöht werden.

An impact analysis of the NEXUS Chest CT clinical decision rule

BACKGROUND

The NEXUS Chest CT clinical decision rules (CDRs) have been proposed to safely guide selective chest CT use in blunt trauma evaluation. We conducted a cost-effectiveness analysis of the NEXUS Chest CT CDR to determine its impact on missed injuries, cost, and radiation exposure.

METHODS

We constructed a decision model comparing two strategies: implementation of the NEXUS Chest CDR vs. usual care in the evaluation of adults with blunt trauma. We derived probabilities, clinical outcomes, effective radiation dose (ERD) from the NEXUS Chest CT validation cohort and costs from the Charge-master at the primary study site. Our primary outcomes were cost and effective radiation dose (ERD) per missed clinically significant injury (CSI).

RESULTS

Using a hypothetical cohort of 1000 adults with blunt chest trauma in each arm, the base case model projected that the implementation of the CDR would result in 161 fewer chest CTs, 0.08 additional missed CSIs, a cost savings of $136,432 and a decrease in 1435 mSv, as compared to Usual Care. To detect one additional CSI, the Usual Care strategy would require 2015 more chest CTs with a cost of $1.8 million and 17,934 mSv more radiation.

CONCLUSIONS

Compared to usual care, implementation of the NEXUS Chest CT Major CDR in the evaluation of adults with blunt trauma would greatly reduce CT associated costs and radiation exposure with a slight increased risk of missed CSIs.

Development of injury risk models to guide CT evaluation in the emergency department after motor vehicle collisions

OBJECTIVE

The clinical evaluation of motor vehicle collision (MVC) victims is challenging and commonly relies on computed tomography (CT) to detect internal injuries. CT scans are financially expensive and each scan exposes the patient to additional ionizing radiation with an associated, albeit low, risk of cancer. Injury risk prediction based on regression modeling has been to be shown to be successful in estimating Injury Severity Scores (ISSs). The objective of this study was to (1) create risk models for internal injuries of occupants involved in MVCs based on CT body regions (head, neck, chest, abdomen/pelvis, cervical spine, thoracic spine, and lumbar spine) and (2) evaluate the performance of these risk prediction models to predict internal injury.

METHODS

All Abbreviated Injury Scale (AIS) 2008 injury codes were classified based on which CT body region would be necessary to scan in order to make the diagnosis. Cases were identified from the NASS-CDS. The NASS-CDS data set was queried for cases of adult occupants who sought medical care and for which key crash characteristics were all present. Forward stepwise logistic regression was performed on data from 2010-2014 to create models predicting risk of internal injury for each CT body region. Injury risk for each region was grouped into 5 levels: very low (<2%), low (2-5%), medium (5-10%), high (10-20%), and very high (20%). The models were then tested using weighted data from 2015 in order to determine whether injury rates fell within the predicted risk level.

RESULTS

The inclusion and exclusion criteria identified 5,477 cases in the NASS-CDS database. Cases from 2010-2014 were used for risk modeling (n = 4,826). Seven internal injury risk models were created based on the CT body regions using data from 2010-2014. These models were tested against data from 2015 (n = 651). In all CT body regions, the majority of occupants fell in the very low or low predicted injury rate groups, except for the head. On average, 57% of patients were classified as very low risk and 15% as low risk for each body region. In most cases the actual rate of injury was within the predicted injury risk range. The 95% confidence interval overlapped with predicting injury risk range in all cases.

CONCLUSION

This study successfully demonstrated the ability for internal injury risk models to accurately identify occupants at low risk for internal injury in individual body regions. This represents a step towards incorporating telemetry data into a clinical tool to guide physicians in the use of CT for the evaluation of MVC victims.

Low Yield of Paired Head and Cervical Spine Computed Tomography in Blunt Trauma Evaluation

BACKGROUND

With increased computed tomography (CT) utilization, clinicians may simultaneously order head and neck CT scans, even when injury is suspected only in one region.

OBJECTIVE

We sought to determine: 1) the frequency of simultaneous ordering of a head CT scan when a neck CT scan is ordered; 2) the yields of simultaneously ordered head and neck CT scans for clinically significant injury (CSI); and 3) whether injury in one region is associated with a higher rate of injury in the other.

METHODS

This was a retrospective study of all adult patients who received neck CT scans (and simultaneously ordered head CT scans) as part of their blunt trauma evaluation at an urban level 1 trauma center in 2013. An expert panel determined CSI of head and neck injuries. We defined yield as number of patients with injury/number of patients who had a CT scan.

RESULTS

Of 3223 patients who met inclusion criteria, 2888 (89.6%) had simultaneously ordered head and neck CT scans. CT yield for CSI in both the head and neck was 0.5% (95% confidence interval [CI] 0.3-0.8%), and the yield for any injury in both the head and neck was 1.4% (95% CI 1.0-1.8%). The yield for CSI in one region was higher when CSI was seen in the other region.

CONCLUSIONS

The yield of CT for CSI in both the head and neck concomitantly is very low. When injury is seen in one region, there is higher likelihood of injury in the other. These findings argue against paired ordering of head and neck CT scans and suggest that CT scans should be ordered individually or when injury is detected in one region.

Feasibility of Informed Consent for Computed Tomography in Acute Trauma Patients

BACKGROUND

Computed tomography (CT) is common for trauma victims, but is usually done without informing patients of potential risks or obtaining informed consent.

OBJECTIVE

The objective of this study was to determine the feasibility of two elements (time and normal level of alertness) necessary for informed consent for CT in adult trauma patients.

METHODS

We conducted this prospective observational, two-phase cohort study at two urban, Level I trauma centers. In the first phase, we determined the median time needed to obtain informed consent for CT by performing sham consent on 11 injured patients at each site. In the second phase, we observed all adult trauma activation cases that presented during specified time blocks and recorded Glasgow Coma Scale (GCS) scores and the time available for consent (TAC) for CT-defined as the time between the end of the secondary trauma survey and when the patient left the resuscitation room to go to CT. We defined, a priori, feasible consent cases as those in which the patient had a GCS of 15 and a TAC greater than the median sham consent time at that site.

RESULTS

The median times for sham CT consent at the two sites were 3:36 and 2:09 minutes:seconds (range = 1:12-4:54). Of the 729 trauma patients enrolled during phase II, 646 (89%) had a CT scan, and of these 646 patients, 461 (71.4% [95% confidence interval = 67.8%- 74.7%]) met feasible consent criteria. Of the 185 patients who failed to meet feasible consent criteria, 171 (92.4%) had a GCS < 15, one (0.5%) had a TAC less than the sham consent time, and 13 (7.0%) had both.

CONCLUSION

We found that informed consent for CT was likely feasible in over two-thirds of acute, adult trauma patients.

Selective chest imaging for blunt trauma patients: The national emergency X-ray utilization studies (NEXUS-chest algorithm)

Chest imaging plays a prominent role in blunt trauma patient evaluation, but indiscriminate imaging is expensive, may delay care, and unnecessarily exposes patients to potentially harmful ionizing radiation. To improve diagnostic chest imaging utilization, we conducted 3 prospective multicenter studies over 12years to derive and validate decision instruments (DIs) to guide the use of chest x-ray (CXR) and chest computed tomography (CT). The first DI, NEXUS Chest x-ray, consists of seven criteria (Age >60years; rapid deceleration mechanism; chest pain; intoxication; altered mental status; distracting painful injury; and chest wall tenderness) and exhibits a sensitivity of 99.0% (95% confidence interval [CI] 98.2-99.4%) and a specificity of 13.3% (95% CI, 12.6%-14.0%) for detecting clinically significant injuries. We developed two NEXUS Chest CT DIs, which are both highly reliable in detecting clinically major injuries (sensitivity of 99.2%; 95% CI 95.4-100%). Designed primarily to focus on detecting major injuries, the NEXUS Chest CT-Major DI consists of six criteria (abnormal CXR; distracting injury; chest wall tenderness; sternal tenderness; thoracic spine tenderness; and scapular tenderness) and exhibits higher specificity (37.9%; 95% CI 35.8-40.1%). Designed to reliability detect both major and minor injuries (sensitivity 95.4%; 95% CI 93.6-96.9%) with resulting lower specificity (25.5%; 95% CI 23.5-27.5%), the NEXUS CT-All rule consists of seven elements (the six NEXUS CT-Major criteria plus rapid deceleration mechanism). The purpose of this review is to synthesize the three DIs into a novel, cohesive summary algorithm with practical implementation recommendations to guide selective chest imaging in adult blunt trauma patients.

Prevalence and Diagnostic Performance of Isolated and Combined NEXUS Chest CT Decision Criteria

OBJECTIVES

The use of chest computed tomography (CT) to evaluate emergency department patients with adult blunt trauma is rising. The NEXUS Chest CT decision instruments are highly sensitive identifiers of adult blunt trauma patients with thoracic injuries. However, many patients without injury exhibit one of more of the criteria so cannot be classified "low risk." We sought to determine screening performance of both individual and combined NEXUS Chest CT criteria as predictors of thoracic injury to inform chest CT imaging decisions in "non-low-risk" patients.

METHODS

This was a secondary analysis of data on patients in the derivation and validation cohorts of the prospective, observational NEXUS Chest CT study, performed September 2011 to May 2014 in 11 Level I trauma centers. Institutional review board approval was obtained at all study sites. Adult blunt trauma patients receiving chest CT were included. The primary outcome was injury and major clinical injury prevalence and screening performance in patients with combinations of one, two, or three of seven individual NEXUS Chest CT criteria.

RESULTS

Across the 11 study sites, rates of chest CT performance ranged from 15.5% to 77.2% (median = 43.6%). We found injuries in 1,493/5,169 patients (28.9%) who had chest CT; 269 patients (5.2%) had major clinical injury (e.g., pneumothorax requiring chest tube). With sensitivity of 73.7 (95% confidence interval [CI] = 68.1 to 78.6) and specificity of 83.9 (95% CI = 83.6 to 84.2) for major clinical injury, abnormal chest-x-ray (CXR) was the single most important screening criterion. When patients had only abnormal CXR, injury and major clinical injury prevalences were 60.7% (95% CI = 52.2% to 68.6%) and 12.9% (95% CI = 8.3% to 19.4%), respectively. Injury and major clinical injury prevalences when any other single criterion alone (other than abnormal CXR) was present were 16.8% (95% CI = 15.2% to 18.6%) and 1.1% (95% CI = 0.1% to 1.8%), respectively. Injury and major clinical injury prevalences among patients when two and three criteria (not abnormal CXR) were present were 25.5% (95% CI = 23.1% to 28.0%) and 3.2% (95% CI = 2.3% to 4.4%) and 34.9% (95% CI = 31.0% to 39.0%) and 2.7% (95% CI = 1.6% to 4.5%), respectively.

CONCLUSIONS

We recommend that clinicians check for the six clinical NEXUS Chest CT criteria and review the CXR (if obtained). If patients have one clinical criterion (other than abnormal CXR), they will have a very low risk of clinically major injury. We recommend that clinicians discuss the potential risks and benefit of chest CT in these cases. The risks of injury and major clinical injury rise incrementally with more criteria, rendering the risk/benefit ratio toward performing CT in most cases. If the patient has an abnormal CXR, the risks of major clinical injury and minor injury are considerably higher than with the other criteria-chest CT may be indicated in cases requiring greater anatomic detail and injury characterization.

Communicating radiation risk to patients and referring physicians in the emergency department setting

Heightened awareness about the radiation risks associated with CT imaging has increased patients' wishes to be informed of these risks, and has motivated efforts to reduce radiation dose and eliminate unnecessary imaging. However, many ordering providers, including emergency physicians, are ill prepared to have an informed discussion with patients about the cancer risks related to medical imaging. Radiologists, who generally have greater training in radiation biology and the risks of radiation, often do not have a face-to-face relationship with the patients who are being imaged. A collaborative approach between emergency physicians and radiologists is suggested to help explain these risks to patients who may have concerns about getting medical imaging.

Overtesting and the Downstream Consequences of Overtreatment: Implications of "Preventing Overdiagnosis" for Emergency Medicine

Overtesting, the downstream consequences of overdiagnosis, and overtreatment of some patients are topics of growing debate within emergency medicine (EM). The "Preventing Overdiagnosis" conference, hosted by The Dartmouth Institute for Health Policy and Clinical Practice, with sponsorship from consumer organizations, medical journals, and academic institutions, is evidence of an expanding interest in this topic. However, EM represents a compellingly unique environment, with increased decision density tied to high stakes for patients and providers with missed or delayed diagnoses in a professional atmosphere that does not tolerate mistakes. This article reviews the relevance of this reductionist paradigm to EM, provides a first-hand synopsis of the first "Preventing Overdiagnosis" conference, and assesses barriers to moving the concept of less test ordering to reality.

Prevalence of Chest Injury With the Presence of NEXUS Chest Criteria: Data to Inform Shared Decisionmaking About Imaging Use

STUDY OBJECTIVE

The NEXUS chest decision instrument identifies a very-low-risk population of patients with blunt trauma for whom chest imaging can be avoided. However, it requires that all 7 National Emergency X-Ray Utilization Study (NEXUS) chest criteria be absent. To inform patient and physician shared decisionmaking about imaging, we describe the test characteristics of individual criteria of the NEXUS chest decision instrument and provide the prevalence of injuries when 1, 2, or 3 of the 7 criteria are present.

METHODS

We conducted this secondary analysis of 2 prospectively collected cohorts of patients with blunt trauma who were older than 14 years and enrolled in NEXUS chest studies between December 2009 and January 2012. Physicians at 9 US Level I trauma centers recorded the presence or absence of the 7 NEXUS chest criteria. We calculated test characteristics of each criterion and combinations of criteria for the outcome measures of major clinical injuries and thoracic injury observed on chest imaging.

RESULTS

We enrolled 21,382 patients, of whom 992 (4.6%) had major clinical injuries and 3,135 (14.7%) had thoracic injuries observed on chest imaging. Sensitivities of individual test characteristics ranged from 15% to 56% for major clinical injury and 14% to 53% for thoracic injury observed on chest imaging, with specificities varying from 71% to 84% for major clinical injury and 67% to 84% for thoracic injury observed on chest imaging. Individual criteria were associated with a prevalence of major clinical injury between 1.9% and 3.8% and of thoracic injury observed on chest imaging between 5.3% and 11.5%.

CONCLUSION

Patients with isolated NEXUS chest criteria have low rates of major clinical injury. The risk of major clinical injury for patients with 2 or 3 factors range from 1.7% to 16.6%, depending on the combination of criteria. Criteria-specific risks could be used to inform shared decisionmaking about the need for imaging by patients and their physicians.

Derivation and validation of two decision instruments for selective chest CT in blunt trauma: a multicenter prospective observational study (NEXUS Chest CT)

BACKGROUND

Unnecessary diagnostic imaging leads to higher costs, longer emergency department stays, and increased patient exposure to ionizing radiation. We sought to prospectively derive and validate two decision instruments (DIs) for selective chest computed tomography (CT) in adult blunt trauma patients.

METHODS AND FINDINGS

From September 2011 to May 2014, we prospectively enrolled blunt trauma patients over 14 y of age presenting to eight US, urban level 1 trauma centers in this observational study. During the derivation phase, physicians recorded the presence or absence of 14 clinical criteria before viewing chest imaging results. We determined injury outcomes by CT radiology readings and categorized injuries as major or minor according to an expert-panel-derived clinical classification scheme. We then employed recursive partitioning to derive two DIs: Chest CT-All maximized sensitivity for all injuries, and Chest CT-Major maximized sensitivity for only major thoracic injuries (while increasing specificity). In the validation phase, we employed similar methodology to prospectively test the performance of both DIs. We enrolled 11,477 patients-6,002 patients in the derivation phase and 5,475 patients in the validation phase. The derived Chest CT-All DI consisted of (1) abnormal chest X-ray, (2) rapid deceleration mechanism, (3) distracting injury, (4) chest wall tenderness, (5) sternal tenderness, (6) thoracic spine tenderness, and (7) scapular tenderness. The Chest CT-Major DI had the same criteria without rapid deceleration mechanism. In the validation phase, Chest CT-All had a sensitivity of 99.2% (95% CI 95.4%-100%), a specificity of 20.8% (95% CI 19.2%-22.4%), and a negative predictive value (NPV) of 99.8% (95% CI 98.9%-100%) for major injury, and a sensitivity of 95.4% (95% CI 93.6%-96.9%), a specificity of 25.5% (95% CI 23.5%-27.5%), and a NPV of 93.9% (95% CI 91.5%-95.8%) for either major or minor injury. Chest CT-Major had a sensitivity of 99.2% (95% CI 95.4%-100%), a specificity of 31.7% (95% CI 29.9%-33.5%), and a NPV of 99.9% (95% CI 99.3%-100%) for major injury and a sensitivity of 90.7% (95% CI 88.3%-92.8%), a specificity of 37.9% (95% CI 35.8%-40.1%), and a NPV of 91.8% (95% CI 89.7%-93.6%) for either major or minor injury. Regarding the limitations of our work, some clinicians may disagree with our injury classification and sensitivity thresholds for injury detection.

CONCLUSIONS

We prospectively derived and validated two DIs (Chest CT-All and Chest CT-Major) that identify blunt trauma patients with clinically significant thoracic injuries with high sensitivity, allowing for a safe reduction of approximately 25%-37% of unnecessary chest CTs. Trauma evaluation protocols that incorporate these DIs may decrease unnecessary costs and radiation exposure in the disproportionately young trauma population.

New clinical decision instruments can and should reduce radiation exposure

In this Perspective linked to Rodriguez and colleagues, Emmanuel Lagarde discusses the importance of decision instruments that can help physicians avoid subjecting patients to radiation exposure from unnecessary CT scans.

A cross-sectional study of doctors', managers' and public representatives' views regarding acceptable level of risk in discharges from the emergency department

BACKGROUND

Discharging a patient from the emergency department (ED) always involves some risk of a poor outcome.

AIM

This study examined the hypothesis that there would be an increasing gradient of risk aversion from physicians through clinicians in management and managers to public representatives regarding an acceptable level of risk when considering discharging a patient from the ED.

METHODS

An internet survey was conducted among 180 consultant physicians, 47 clinicians involved in management, 143 senior healthcare managers and 418 public representatives in Ireland. Subjects asked to assess three clinical vignettes for the level of risk for death within the next week that could have been prevented by admission at which discharge from the ED would be acceptable. Choices ranged from 1/100 risk of death to 'no risk of death is acceptable'. The median of each subject's responses was the primary outcome measure.

RESULTS

The response rates were 64% for consultant physicians, 57% for clinicians in management, 53% for managers and 29% for public representatives. The median risk choice (interquartile range) was 1/1000 (1/500-1/5000), 1/1000 (1/500-1/10,000), 1/5000 (1/1000-1/10,000) and 1/10,000 (1/1000-0) in the respective groups (Jonckheere-Terpstra test P < 0.0001). All pairwise comparisons between doctors and managers or public representatives were significant. Older clinicians were significantly more risk tolerant than younger clinicians.

CONCLUSIONS

There are significant differences in risk tolerance when considering discharge from the ED between different groups with doctors being most risk tolerant and politicians most risk averse.